The ability to raise or lower bank capital requirements is one of the potent weapons in the armory of the modern “macroprudential” policy maker, the relatively new species of official—usually a central banker–charged with safeguarding the stability of the financial system. Jacking up capital requirements should slow runaway lending during a credit boom and ensure lenders can weather any losses; lowering them in a downturn should open the credit spigot to needy households and firms.

A paper published Friday by the Bank of England examines how changes in capital requirements between 1990 and 2011 affected bank lending in the U.K. It contains some interesting findings, although the authors stress that what happened under the regulatory framework and economic conditions in place during the 20 or so years they looked at might not necessarily happen if capital requirements were to be raised in a similar way today.

They found that the thing banks cut back on the most when capital requirements were raised was lending to commercial real estate, which accounted for about 11% of the overall stock of loans in the economy in 2011. Next came lending to nonfinancial firms, then mortgage lending, which accounted for almost two-thirds of bank loans. Unsecured lending to households didn’t appear to be particularly affected by higher capital requirements, the authors found.

The study found that raising capital requirements by one percentage point cut the rate of growth of commercial real estate lending in the U.K. over the next 12 months by eight percentage points, roughly twice the pullback in lending to other parts of the corporate sector. They checked what happened if the crisis years were excluded: lending to corporates didn’t slow quite as much.

Once again, the authors stress that it would be unwise to infer that banks would respond to higher capital requirements in the same way today. But it does underscore that blanket increases in capital requirements are likely to affect types of lending differently, which perhaps strengthens the case for targeting capital changes at troublesome sectors.

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